Management of heat conduction using phonononic regions formed with void nanostructures

ABSTRACT

A gas turbine engine component formed of material having phononic regions. The phononic regions are formed of void nanostructures. The phononic regions modify the behavior of the phonons and manage heat conduction.

BACKGROUND

Disclosed embodiments are primarily related to gas turbine engines and,more particularly to phonon management in gas turbine engines. However,the disclosed embodiments may also be used in other heat impacteddevices, structures or environments.

2. Description of the Related Art

Gas turbines engines comprise a casing or cylinder for housing acompressor section, a combustion section, and a turbine section. Asupply of air is compressed in the compressor section and directed intothe combustion section. The compressed air enters the combustion inletand is mixed with fuel. The air/fuel mixture is then combusted toproduce high temperature and high pressure gas. This working gas thentravels past the combustor transition and into the turbine section ofthe turbine.

Generally, the turbine section comprises rows of vanes which direct theworking gas to the airfoil portions of the turbine blades. The workinggas travels through the turbine section, causing the turbine blades torotate, thereby turning a rotor in power generation applications ordirecting the working gas through a nozzle in propulsion applications. Ahigh efficiency of a combustion turbine is achieved by heating the gasflowing through the combustion section to as high a temperature as ispractical. The hot gas, however, may degrade the various metal turbinecomponents, such as the combustor, transition ducts, vanes, ringsegments and turbine blades that it passes when flowing through theturbine.

For this reason, strategies have been developed to protect turbinecomponents from extreme temperatures such as the development andselection of high temperature materials adapted to withstand theseextreme temperatures and cooling strategies to keep the componentsadequately cooled during operation.

Some of the components used in the gas turbine engines are metallic andtherefore have very high heat conductivity. Insulating materials, suchas ceramic may also be used for heat management, but their propertiessometimes prevent them from solely being used as components. Therefore,providing heat management to improve the efficiency and life span ofcomponents and the gas turbine engines is further needed. Of course, theheat management techniques and inventions described herein are notlimited to use in context of gas turbine engines, but are alsoapplicable to other heat impacted devices, structures or environments.

SUMMARY

Briefly described, aspects of the present disclosure relate to materialsand structures for managing heat conduction in components. For examplegas turbine engines, kilns, smelting operations and high temperatureauxiliary equipment.

An aspect of the disclosure may be a gas turbine engine having a gasturbine engine component having a first material, wherein phononictransmittal through the first material forms a first phononic wave; anda phononic region located within the gas turbine engine component,wherein the phononic region is a void nanostructure formed in the firstmaterial, wherein phononic transmittal through the void nanostructuremodifies behavior of the phonons of the first phononic wave therebymanaging heat conduction.

Another aspect of the present disclosure may be a method for managingheat conduction in a gas turbine engine comprising forming a phononicregion by forming a void nanostructure in a first material of a gasturbine engine component, wherein phononic transmittal through the firstmaterial forms a first phononic wave; and modifying behavior of phononstransmitted through the first material when the phonons are transmittedto the void forming the phononic region thereby managing heatconduction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of phonons interacting with a phononic region wherea wave property is modified.

FIG. 2 is a diagram of phonons interacting with a phononic region wherethe mode of propagation is altered.

FIG. 3 is a diagram of phonons interacting with a phononic region wherethe movement direction of the phonon is changed.

FIG. 4 is a diagram of phonons interacting with a phononic region wherethe phonons are scattered.

FIG. 5 is a diagram of phonons interacting with a phononic region wherewaves are refracted.

FIG. 6 is a diagram of phonons interacting with a phononic region wherethe phonons are dissipated.

FIG. 7 is a diagram illustrating a material having phononic regionsformed of void nanostructures that are void spheres in a randomdistribution.

FIG. 8 is a diagram illustrating a material having phononic regionsformed of void nanostructures that are void spheres in an orderedarrangement.

FIG. 9 is a diagram illustrating boundaries of phononic regions of voidnanostructures that are void columns.

FIG. 10 shows an example of a nanomesh formed on the material of a gasturbine engine component.

FIG. 11 shows an example of a nanomesh grid formed on the material of agas turbine engine component.

FIG. 12 shows a diagram of a nanomesh grid formed on the material of agas turbine engine component.

DETAILED DESCRIPTION

To facilitate an understanding of embodiments, principles, and featuresof the present disclosure, they are explained hereinafter with referenceto implementation in illustrative embodiments. Embodiments of thepresent disclosure, however, are not limited to use in the describedsystems or methods.

The items described hereinafter as making up the various embodiments areintended to be illustrative and not restrictive. Many suitable itemsthat would perform the same or a similar function as the items describedherein are intended to be embraced within the scope of embodiments ofthe present disclosure.

As disclosed herein, the materials used in the gas turbine enginespermit the thermal conductivity of pieces to be modified, such as bybeing reduced in size, without changing the chemical structure in themajority of the material. Management of heat conduction can be achievedthrough nanostructure modification to portions of the existing gasturbine engine components. There is no need for a large scale bulkmaterial or chemical changes; however smaller scale modificationsconsistent with aspects of the instant invention may be made to gasturbine engine components.

FIG. 1 shows a diagram illustrating the transmission of phonons 10 intoa material 20 that is forming part of a gas turbine engine component 100that can be used in a gas turbine engine. The gas turbine enginecomponent 100 may be a transition duct, liner, part of the combustor,vanes, blades, rings and other gas turbine structures for which heatmanagement would be advantageous. It should also be understood that inaddition to gas turbine engine components 100, the management of heatconduction disclosed herein can be applied to other devices for whichheat management is important, for example, marine based turbines,aerospace turbines boilers, engine bells, heat management devices,internal combustion engines, kilns, smelting operations and any otheritem wherein heat conduction is a design consideration.

The material 20 discussed herein is a metallic material, however itshould be understood that other types of materials may be used, such asceramic, metallic glasses and composite materials, when given dueconsideration for their material properties consistent with aspects ofthe instant invention. A phonon 10 is generally and herein understoodand defined as a quantum of energy associated with a compressional,longitudinal, or other mechanical or electro-mechanical wave such assound or a vibration of a crystal lattice. Transmissions of phonons 10collectively transmit heat. The transmissions of phonons 10 form wavesin the material 20 as they propagate through the material 20.

In FIG. 1, the phonons 10 are transmitted through the material 20 at afirst phononic wave W1. Formed in the material 20 is a phononic region30. The phononic region 30 is designed to modify the behavior of thephonons 10 as they propagate in the one dimensional (1D), twodimensional (2D) and/or three dimensional (3D) spatial regions in thematerial 20. The phononic region 30 may modify the behavior of phonons10 so that they scatter, change direction, change between propagationmodes (e.g. change from compression waves to travelling waves), reflect,refract, filter by frequency, and/or dissipate. The modification of thebehavior of the phonons 10 manages the heat conduction in the gasturbine engine component 100. The phononic region 30 is a voidnanostructure formed within the material 20. The void nanostructure isdesigned to be placed within the material 20 in such a manner as tomodify the behavior of phonons 10 as they propagate through the material20 so that heat conduction through the material 20 is controlled. Thevoid nanostructures can be formed as divots, void spheres, void channelsor other modifications to the material.

Still referring to FIG. 1, the modification of behavior of the phonons10 by the phononic region 30 may create a second phononic wave W2. Forexample, the first phononic wave W1 propagates through the material 20.As the first phononic wave W1 propagates through the material 20 thefirst phononic wave W1 may have the property of having a first frequencyλ₁. When the first phononic wave W1 interacts with the phononic region30 the behavior of the phonons 10 may form a second phononic wave W2having the property of having a second frequency λ₂. As the phonons 10exit from the phononic region 30 and propagate through the material 20they may continue to propagate at the first frequency λ₁.

The transition from the first frequency λ₁ to the second frequency λ₂and then back to the first frequency λ₁, helps manage the heatconduction in the material 20. Further, by interspersing the material 20with a number of phononic regions 30 the fluctuation can disrupt thetransmission of phonons 10 through the material 20 so as to manage thepropagation of phonons 10.

FIG. 2 shows a phononic region 30 that modifies the behavior of thefirst phononic wave W1 to a second phononic wave W2 by changing theproperty of its mode of propagation. In FIG. 2 the first phononic waveW1 is altered from a travelling wave to the second phonic wave W2 whichis a compression wave. However it should be understood that it iscontemplated that compression waves could be modified to becometravelling waves. By modifying the mode of propagation of the waves theheat conduction through the material 20 may be managed.

FIG. 3 shows a phononic region 30 that modifies the behavior of thephonons 10 by altering the direction of propagation. Phonons 10 may bemoving in one direction D1 through material 20 and then change directionto direction D2 as they enter into phononic region 30. By modifying thedirection of movement of the phonons 10 the heat conduction through thematerial 20 may be managed.

FIG. 4 shows a phononic region 30 that modifies the behavior of thephonons 10 so that the phonons 10 are scattered when they enter thephononic region 30 from the material 20. By scattering it is meant thateach phonon 10 that enters the phononic region 30 in direction D1 maypropagate in a random different direction D2, D3, etc. By modifying thescattering of the phonons 10 the heat conduction through the material 20may be managed.

FIG. 5 shows a first phononic wave W1 moving through material 20. Whenthe first phononic wave W1 reaches the phononic region 30 the firstphononic wave W1 is modified so that it is refracted and becomes secondphononic wave W2 as it passes through the phononic region 30. As thesecond phononic wave W2 exits the phononic region 30 the phononic waveW2 may be refracted and become a third phononic wave W3. By having thephononic region 30 refract the first phononic wave W1 the heatconduction through the material 20 may be managed.

FIG. 6 shows the phononic region 30 located within the material 20causing phonons 10 from the first phononic wave W1 to dissipate as itexits the material 20. By “dissipate” it is meant that at least some ofthe phonons 10 cease to travel through the phononic region 30 or ceaseto exist. By having the phononic region 30 dissipate the phonons 10 theheat conduction through the material 20 may be managed.

FIG. 7 shows an example of the phononic region 30 formed by voidnanostructures within the material 20. It should be understood that thevoid nanostructure forms the entirety of the phononic region 30.However, various phononic regions 30 may be formed from more than onetype of void nanostructure. For example, as discussed herein the voidnanostructure forming the phononic region 30 may be a void sphere 35formed within the material 20. In addition to a void sphere 35, othershapes for the void nanostructures may be formed such as void channels40 or nanovoid divots 45, as well as, amorphous shapes or otherpolygonal shapes.

The material 20 may be metallic in nature and may form a gas turbineengine component 100 or the component of another device wherein heatmanagement may be need. Within the material 20 the phononic regions 30may be formed as void spheres 35 within the material 20. FIG. 7 showsthe void spheres 35 randomly dispersed throughout the material 20. Thevoid spheres 35 may have a diameter of between 5 nm-1000 nm. Theplacement and size of the void spheres 35 is determined based upon howheat conduction in the gas turbine engine component 100 will be managed.

FIG. 8 shows an alternative embodiment of the phononic regions 30 formedof void nanostructures where the void spheres 35 are positioned withinthe material in an orderly manner. In this example the void spheres 35are organized so that they form rows of the void spheres 35. The voidspheres 35 may have a diameter of between 5 nm-1000 nm. The placementand size of the void spheres 35 is determined based upon how heatconduction in the gas turbine engine component 100 will be managed.

FIG. 9 is an alternative embodiment having phononic regions 30 formed asvoid channels 40 within the material 20. The void channels 40 may have awidth of between 5 nm-1000 nm. The length of the void channel 40 mayvary depending on the size of the gas turbine engine component 100,however generally a size of between 100 um-10 cm is contemplated.However, the void channel 40 may be between 10 um and 100 cm. Theplacement and size of the void channels 40 is determined based upon howheat conduction in the gas turbine engine component 100 will be managed.

Introduction of sharp changes in the acoustic impedance experienced byphonons 10 propagating through the phononic regions 30 can beinstantiated by the void spheres 35 or void channels 40 formed in thematerial 20. The phononic regions 30 can be formed in various layers ofthe material 20. When the phononic region 30 is incorporated into asubsection of a material 20 with resolutions in the 5-1000 nm range, thevoid nanostructures that form the phononic region 30 will cause thephonons 10 to behave in one of the manners discussed above in referenceto FIGS. 1-6. This size correlates with phononic vibration frequenciesof approximately 500 GHz to 100 THZ. Because the phononic regions 30will have differing phononic impedances than the material 20, they willmodify behavior of the propagating phonons 10 in the material 20,thereby disrupting, reducing and/or managing heat conduction. Thesetechniques can also be used to direct heat conduction in desireddirections by creating paths of optimal propagation for heat-inducingphonons 10 that are surrounded by phononic regions 30.

In each of the above possible ways of managing the heat conduction shownin FIGS. 1-6, phonons 10 interacting with phononic regions 30 on thesame scale as their wavelength, can modify behavior of phonons 10 toimpede propagation of phonons 10 and thus manage heat conduction. Thepatterns formed by the phononic regions 30 can be used to obtain themodified behavior of the phonons 10 that is desired. For example,patterns of phononic regions 30 parallel to the propagation directioncan channel the phonons 10. Patterns of phononic regions 30 normal tothe phonons 10 can reflect them. Patterns of phononic regions 30 at anangle with respect to the propagation direction can scatter or reflectat an angle, spots of acoustic impedance change could cause scattering,etc.

As discussed above the phononic regions 30 may be used in metals andother crystalline structures, as well as ceramics in which voidnanostructures may be created. In metals especially at temperaturesabove 400° C., the majority carrier is electrons. The technique formodifying behavior of the phonons 10 is likely to manage phonons 10directly more so than thermal free electrons in metals. However,electron propagation may also be affected by the phononic regions 30, intwo possible ways. One, electrons in metals are constantly exchangingtheir energies with phonons 10, so management of the phonons 10 has aneffect on electrical propagation. Two, if the electron propagation hasany frequency component, it would likely be of similar frequencies asthe phonon 10, due to similar interactions that the electrons will havewith crystalline structures. In metals control of phonons 10 may havesignificant impacts on heat conduction that is mediated by thermal freeelectrons.

FIG. 10 shows an example of a nanomesh 50 formed on material 20 of thegas turbine engine component 100. In particular, for example, thenanonmesh 50 may be formed on the surface of a vane. The vane may be amodified vane from an existing gas turbine engine component 100, oralternatively the vane may have been formed with the nanomesh 50.Additionally the design of the vane may be modified from an existingvane design or alternatively designed in such a fashion so as to takeadvantage of the use of the nanomesh 50. The dark spheres are phononicregions 30 that are void nanostructures formed as void spheres 35 withinthe material 20 of gas turbine engine component 100. The void spheres 35have diameters that fall within the range of 5-1000 nm. In the exampleshown the diameters may be in the range 250 nm-400 nm. By having thevoid spheres 35, phonons 10 propagating through the material 20impacting the nanomesh 50 can be managed. The nanomesh 50 can modify thebehavior of the phonons 10 by disrupting the propagation and cause thephonons 10 to behave in the manner shown in FIGS. 1-6. The desiredbehavior can be caused by arranging the nanonmesh 50 to form patterns inthe material 20 that they can be used to manage heat conduction.

FIG. 11 shows an example of a nanomesh grid 55 formed on the surface ofa material 20 on the gas turbine engine component 100. For example, ananomesh grid 55 may be formed on a transition duct. The transition ductmay be a modified component from an existing gas turbine enginecomponent 100, or alternatively the transition duct may have been formedwith the nanomesh grid 55. Additionally the design of the transitionduct may be modified from an existing combustor design or alternativelydesigned in such a fashion so as to take advantage of the use of thenanomesh grid 55. The nanomesh grid 55 is formed from phononic regions30 arranged as nanovoid divots 45 within the material 20. The nanovoiddivots 45 may be formed by lasers pock-marking the surface of thematerial 20 and then placing another layer of the material 20 on top ofthe layer with the nanovoid divots 40 formed. The nanovoid divots 40 maybe formed so as to have a diameter of between 5-1000 nm. In the exampleshown the diameters of nanovoid divots 40 may be in the range of 10nm-40 nm. By having the nanovoid divots 45, the phonons 10 propagatingthrough the material 20 impacting the nanomesh grid 55 can be managed.The nanomesh grid 55 can modify the behavior of the phonons 10 bydisrupting the propagation and cause the phonons 10 to behave in themanner shown in FIGS. 1-6.

FIG. 12 is diagram illustrating layered placement of a nanomesh grid 55on a material 20 forming the gas turbine engine component 100. Forexample, the nanomesh grid 55 may be formed on the interior surface of acombustor. The combustor may be a modified component from an existinggas turbine engine component 100. Additionally the design of thecombustor may be modified from an existing combustor design oralternatively designed in such a fashion so as to take advantage of theuse of the nanomesh grid 55.

On the surface of the material 20 the nanomesh grid 55 is formed. Thethickness of the material 20 may be between 1 cm to 10 cm. The thicknessof the nanomesh grid 55 may be between 5-1000 nm. The nanomesh grid 55may be formed in one of the manners discussed above, for example thenanomesh grid 55 may be formed by adding nanovoid divots 40 to anexisting gas turbine engine component 100. On the surface of thenanomesh grid 55 a thermal barrier 54 may be placed. The thickness ofthe thermal barrier 54 may be between 1 mm to 5 cm. The thermal barrier54 may be made of a heat resistant material, such as ceramic. Onceformed the layered structure can be used to manage the propagation ofthe heat from the interior of the combustor. This can help reduce thestresses that heat may generate in the material 20 and can extend thelife span of gas turbine engine components 100.

While embodiments of the present disclosure have been disclosed inexemplary forms, it will be apparent to those skilled in the art thatmany modifications, additions, and deletions can be made therein withoutdeparting from the spirit and scope of the invention and itsequivalents, as set forth in the following claims.

1-18. (canceled)
 19. A gas turbine engine component comprising: a firstregion of a first material; and a phononic region comprising voidnanostrcutures within the first material; wherein phononic transmittalof phonons through the first material forms a first phononic wave havingthe phonons; and wherein, upon transmittal of the first phononic wave tothe phononic region, the phononic region is configured to modify abehavior of the phonons of the first phononic wave.
 20. The gas turbineengine component of claim 19, wherein the first phononic wave has afirst property, wherein the phononic region is configured to thebehavior of the phonons of the first phononic wave to form a secondphononic wave having a second property different than the first propertyof the first phononic wave.
 21. The gas turbine engine component ofclaim 20, wherein the first property and the second property arefrequency.
 22. The gas turbine engine component of claim 20, wherein thefirst property and the second property are modes of propagation.
 23. Thegas turbine engine component of claim 19, wherein the phononic regionmodifies the behavior of the phonons of the first phononic wave so thatthe phonons of the first phononic wave change direction of propagation.24. The gas turbine engine component of claim 19, wherein the phononicregion modifies the behavior of the phonons of the first phononic waveso that the phonons of the first phononic wave scatter.
 25. The gasturbine engine component of claim 19, wherein the phononic regionmodifies the behavior of the phonons of the first phononic wave so thatthe phonons of the first phononic wave are reflected, refracted, ordissipated.
 26. The gas turbine engine component of claim 19, whereinthe phononic region is selected from the group consisting of a voidsphere, a nanovoid divot, and void channel.
 27. The gas turbine enginecomponent of claim 26, wherein the void nanostructures comprise voidspheres having a diameter of from 5-1000 nm.
 28. The gas turbinecomponent of claim 27, wherein the void spheres are formed in rowswithin the first material.
 29. The gas turbine engine component of claim26, wherein the void nanostructures comprises void columns having adiameter of from 5-1000 nm.
 30. A method for controlling heat conductionin a gas turbine engine comprising: forming a phononic region within afirst region of a first material of a gas turbine engine component,wherein the phononic region comprises void nanostructures; transmittingphonons through the first material to form a first phononic wave havingthe phonons; transmitting the first phononic wave to the phononicregion, and modifying a behavior of the phonons of the first phononicwave in the phononic region to manage heat conduction.
 31. The method ofclaim 30, wherein the first phononic wave has a first property, whereinthe phononic region modifies the behavior of the phonons of the firstphononic wave to form a second phononic wave having a second propertydifferent than the first property of the first phononic wave.
 32. Themethod of claim 30, wherein the first property and the second propertyare frequency or modes of propagation.
 33. The method of claim 30,wherein the modified behavior of the phonons of the first phononic waveis a changed direction of propagation of the phonons of the firstphononic wave.
 34. The method of claim 30, wherein the modified behaviorof the phonons of the first phononic wave is at least one of scattering,reflection, refraction, or dissipation of the phonons of the firstphononic wave.
 35. The method of claim 30, wherein the phononic regionis selected from the group consisting of a void sphere, a nanovoiddivot, and void channel.
 36. The method of claim 35, wherein the voidnanostructures comprise void spheres having a diameter of from 5-1000nm.
 37. The method of claim 36, wherein the void spheres are formed inrows within the first material.
 38. The method of claim 35, wherein thevoid nanostructures comprise void columns having a diameter of from5-1000 nm.